Jasjeet Sekhon benchmarked Linux and MacOS X on the MacBook Pro using his statistical software, and finds that "Linux is found to be much faster than Apple's OS X for statistical computing. For example, in one benchmark Linux is more than twice as fast." Earlier, he ran tests on a G5 and an Opteron, and conlcuded: "Those results were terrible for OS X and not particularly good for the G5 (970) chip. For example, my 2.7 pound Pentium-M Linux laptop is faster than my 44 pound G5 running OS X. The floating point performance of the 970 chip leaves much to be desired, but OS X makes the performance problem significantly worse."

I think you all are missing the point. This has nothing to do with desktops or servers or guis. What it has to do with is a long running debate about the way the Darwin kernel handles certain types of calls being very very expensive. There were benchmarks of FreeBSD vs. Darwin on PPC which showed this. There were benchmarks of Linux vs. Darwin on PPC which showed this. However once you start benchmarking Linux on its home platform against Darwin the differences are large.

The point is that either:
1) Darwin is going to be a low performance kernel for a long time
2) Apple is going to need to invent computer science techniques for handling these problems
3) The darwin kernel needs to be reengineered.

I believe jeffb it's right on this. The topic shouldn't be "look how slow is OSX compared to Linux in this kind of calculation" but "Look how performance-unpotimized is OSX kernel". If we start comparing the Oses, it's all going to be "my OS is faster" "my Os is slower but gives better experience"... we're not going anywhere. In the end, while I still believe productivity isn't completely related to speed and that a rational and well designed interface could compensate some performance issues, I also believe OSX kernel could use some speed improvements.

(Which is why I was completely puzzled by the latest Vista build which is not only slow (as ervery beta is anyway) but it's also taking steps in creating the interface less streamlined and more cumbersome, resulting in less and less productivity (like all those modal security requesters. Every time I launch a control app the computer comes to a stop... might have some sense, but it simply doesn't work for me))